Ongoing efforts have been directed to making polyolefin pipe compositions, particularly high density polyethylene pipe compositions. A goal is for the resin to be made economically and efficiently, while providing a pipe with a desirable balance of properties.
U.S. Pat. Nos. 7,037,977, 6,090,893, and 7,193,017, and U.S. Patent Application Publications Nos. US 2007/027611, US 2004/0157988, and US 2005/0234197 relate to polyethylene pipe resins. There is a need for a high strength polyethylene composition exhibiting a desirable balance of properties including in a class of embodiments a higher melt strength.